1. Field of the Invention
This invention relates to a cement composition and building blocks formed therefrom.
2. Description of the Prior Art
Today's building industry is experimenting with building blocks of many different compositions. Primarily, buildings are constructed of precast concrete blocks made with a variety of grades and types of cements. In order to impart greater insulation qualities to concrete blocks, they have been formed with hollow interiors into which insulating foam or the like has been placed. Others impart greater insulation value by adding insulators to the cement mixture. Examples of such additives commonly used are expanded polystyrene beads, perlite minerals and the like. These additives have the dual advantage of increasing the insulation qualities of the block as well as making the block lightweight.
Two problems have occurred with blocks made with the aforementioned materials. First, as more insulation material is added to the cement, the block becomes lighter and less strong. Second, polystyrene beads and perlite both tend to float when mixed into the water based cement. U.S. Pat. No. 2,727,827 to Charikof addresses the problem of floating perlite by coating the mineral with an air release inhibitor.
Other additives are also commonly added to perlite/cement mixtures. Additionally, perlite has little compression strength when used in quantities to provide good insulation qualities. Also, perlite is an expensive additive when used in quantities necessary for good insulation.
No prior art is known which overcomes the problems of both floating and compression of cement additives by adding ceramic aggregate or grog to cement. Ceramic aggregates do not float and need no additives to mix completely with the cement. Presently there is no known composition for building blocks which combines cement with inexpensive and plentiful ceramic materials.